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Hello,
I have an issue when using an O365 account and sending emails from an application.
The application has been suitable to use tls/starttls, port 587, ect.
When entering an email account and password, the following message occurs:
"535: 5.7.3 Authentication unsuccessful"
I would like to understand, what are the mininal features of an O365 account so that it can be used from another application.
I have performed different tests, which allow me to indicate that the account is Ok.
Thank you.
Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
u can try turn off AZURE certification. i did it and it works.
Also u need to go to Microsoft 365 admin center
Hello,
I have an issue when using an O365 account and sending emails from an application.
The application has been suitable to use tls/starttls, port 587, ect.
When entering an email account and password, the following message occurs:
"535: 5.7.3 Authentication unsuccessful"
I would like to understand, what are the mininal features of an O365 account so that it can be used from another application.
I have performed different tests, which allow me to indicate that the account is Ok.
Thank you.
Check your mail's extension, try replacing .com with .co.in, this worked for me
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Jarrid's answer works perfectly for me.
This whole issue is more like a bug in Microsoft outlook admin. In the admin page, I can see the email account has 'SMTP Authentication' ticked. However, when run commands from Jarrid's answer, it shows the value is unset.
I had a same issue with version 1.22, we used that version because the compatibility with olds OS like WinXP that supports until .NET Framework 4.0.0.
Following your suggestion I updated the version of MailKit, and I can confirm that since version 2.0.0 of MailKit the bug is solved.
Thanks for your answer.